This relates generally to imaging systems, and more particularly, to imaging systems with through-oxide vias (TOVs).
Modern electronic devices such as cellular telephones, cameras, and computers often use digital image sensors. Imaging systems (i.e., image sensors) often include a two-dimensional array of image sensing pixels. Each pixel typically includes a photosensitive element such as a photodiode that receives incident photons (light) and converts the photons into electrical signals. The imaging system contains an image sensor die with an image sensor integrated circuit and an array of photodiodes. The image sensor die is mounted on a digital signal processor (DSP) die.
Circuitry within the image sensor die may be coupled to circuitry within the digital signal processor die using through-oxide vias (i.e., metal via structures formed through at least a first oxide layer in the image sensor die and at least a second oxide layer in the DSP die). The amount of time, space, efficiency, and cost for forming via connections in the integrated circuits may, however, be limited. In conventional imaging systems, the steps for forming through-oxide via structures connecting the circuitry in the image sensor die to the circuitry in the DSP die are inefficient and costly.
It would therefore be desirable to provide improved ways of forming via connections in imaging systems.